The communications industry is rapidly changing to adjust to emerging technologies and ever increasing customer demand. This customer demand for new applications and increased performance of existing applications is driving communications network and system providers to employ networks and systems having greater speed and capacity (e.g., greater bandwidth). In trying to achieve these goals, a common approach taken by many communications providers is to use packet switching technology.
Border Gateway Protocol (BGP) is a routing protocol of the Internet that maintains a table of IP addresses (i.e., prefixes) which designate network reachability among autonomous systems (AS's). As used herein, an AS is a connected group of one or more IP prefixes run by one or more network operators which has a single and clearly defined routing policy. As used herein, the term “BGP” refers to all forms of BGP, including internal-BGP and external-BGP. Each BGP advertised route must be unique, otherwise, a subsequent advertisement of the route will consider it the same, and overwrite any previous information received about the route. BGP extensions advertise routes for a Virtual Private Network (VPN). A VPN-IPv4 address is a 12-byte string, beginning with an 8-byte Route Distinguisher (RD) and ending with a 4-byte IPv4 address. If several VPNs use the same IPv4 address prefix, these will be translated into unique VPN-IPv4 address prefixes, making it possible for BGP to carry several completely different routes to that IP address.